Green synthesis, structure-activity relationships, in silico molecular docking, and antifungal activities of novel prenylated chalcones.

A series of 16 novel prenylated chalcones (5A-5P) was synthesized by microwave-assisted green synthesis using 5-prenyloxy-2-hydroxyacetophenone and different benzaldehydes. Comparisons were also performed between the microwave and conventional methods in terms of the reaction times and yields of all compounds, where the reaction times in the microwave and conventional methods were 1-4 min and 12-48 h, respectively. The synthesized compounds were characterized using different spectroscopic techniques, including IR, 1H-NMR, 13C-NMR, and LC-HRMS. The antifungal activities of all compounds were evaluated against Sclerotium rolfsii and Fusarium oxysporum under in vitro conditions and were additionally supported by structure-activity relationship (SAR) and molecular docking studies. Out of the 16 compounds screened, 2'-hydroxy-4-benzyloxy-5'-O-prenylchalcone (5P) showed the highest activity against both S. rolfsii and F. oxysporum, with ED50 of 25.02 and 31.87 mg/L, respectively. The molecular docking studies of the prenylated chalcones within the active sites of the EF1α and RPB2 gene sequences and FoCut5a sequence as the respective receptors for S. rolfsii and F. oxysporum revealed the importance of the compounds, where the binding energies of the docked molecules ranged from -38.3538 to -26.6837 kcal/mol for S. rolfsii and -43.400 to -23.839 kcal/mol for F. oxysporum. Additional docking parameters showed that these compounds formed stable complexes with the protein molecules.

Fabrication of high performance based deep-blue OLED with benzodioxin-6-amine-styryl-triphenylamine and carbazole hosts as electroluminescent materials.

The present study reports synthesis of phenathroimidazole derivatives structures following donor-acceptor relation for high performance deep-blue light emitting diodes. Herein, methyl substituted benzodioxin-6-amine phenanthroimidazoles Cz-SBDPI and TPA-SBDPI derivatives that provide the blue light were designed and synthesized. These Cz-SBDPI and TPA-SBDPI show higher glass transition (Tg) temperatures of 199 and 194 °C and demonstrate enhanced thermal properties. Apart from enhanced thermal stability these compounds also exhibit superior photophysical, electrochemical and electroluminescent properties. The non-doped carbazole based device display improved electroluminescent performances than those of TPA-based devices. The strong orbital-coupling due to decreased energy barrier between Cz-SBDPI transitions result in deep blue emission with CIE-0.15, 0.06. For non-doped Cz-SBDPI device; high L (brightness):12,984 cd/m2; ηc (current efficiency): 5.9 cd/A; ηp (power efficiency): 5.7 lm/W and ηex (external quantum efficiency): 6.2% was observed. The results show that the D-A emitters can serve as simple but also as an effective approach to devise cheap electroluminescent materials that has high efficiency and can serve as OLED devices.

The extent of microplastic pollution along the eastern coast of India: Focussing on marine waters, beach sand, and fish.

In this study, for the first time, we evaluated microplastic contamination in water, beach sand, and fish samples collected from the seven most famous and crowded beaches of the eastern coast of India, which cover around 1200 km. The average number of microplastics found was 80 ± 33 microplastics/m3 and 4 ± 2 microplastics/kg dry weight with a numerical abundance of polyethylene and polystyrene for water and sand samples, respectively. The polymer hazard index score, which represents the severity of the microplastics scenario in the studied locations, depicts that this coastline falls under hazard levels IV and V (most hazardous) for water and sand samples, respectively. The study revealed that approximately 30 % of the commercially important fishes collected from the locations contained microplastics with polyethylene terephthalate and polypropylene being the most abundant types. Rastrelliger kanagurta and Sardinella gibbosa were identified as the most polluted species.

Collagen Biocomposites Derived from Fish Waste: Doped and Cross-Linked with Functionalized Fe3O4 Nanoparticles and Their Comparative Studies with a Green Approach.

Collagen-based nanobiocomposites can reabsorb and are biodegradable. These properties are effectively controlled by the number of cross-links. This study demonstrates an effortless and proficient approach for the functionalization of Fe3O4 NPs for cross-linking collagen obtained from biowaste, viz., fish scales of Lates Calcarifer, a marine origin. The size of Fe3O4 NPs (10-40 nm) was confirmed using particle size analysis. The physico-chemical properties of the aminosilane-coated Fe3O4 NPs cross-linked via succinylated collagen (FFCSC) were characterized using different analytical techniques and compared with succinylated collagen doped with Fe3O4 NPs (FDSC). Thermogravimetric analysis indicates cross-linked product FFCSC to be more stable than the FDSC. Also, the antibacterial effect was more pronounced for FFCSC than for FDSC nanobiocomposites. FFCSC exhibited improved mechanical properties which are essential for materials used for wound dressing purposes. Moreover, the cell viability of fibroblasts (3T3-L1) and their morphology studied by SEM and fluorescence microscopy showed biocompatibility of both FDSC and FFCSC. Thus, the current investigation, involves a waste to wealth approach where the collagen-based nanobiocomposites present an easy way to recycle the biowaste to value-added products using simple and clean methods, which are suitable for use in biomedical and environmental applications.

RNAi-mediated knockdown of gut receptor-like genes prohibitin and α-amylase altered the susceptibility of Galleria mellonella to Cry1AcF toxin.

BACKGROUND: Due to the prolonged usage of Bt-based biopesticides and Bt-transgenic crops worldwide, insects are continually developing resistance against Cry toxins. This resistance may occur if any mechanistic step in the insecticidal process is disrupted possibly because of the alteration in Cry-receptor binding affinity due to mutation in receptor genes. Compared to other lepidopteran insects, Cry receptor-related research has made asymmetric progress in the model insect Galleria mellonella. RESULTS: Present study describes the molecular characterization and functional analysis of five Cry toxin receptor-related genes (prohibitin, GLTP, α-amylase, ADAM and UDP-GT) and a gut repair gene (arylphorin) from the gut tissues of G. mellonella. Protein-protein docking analysis revealed that Cry1AcF putatively binds with all the five candidate proteins, suggesting their receptor-like function. These receptor-like genes were significantly overexpressed in the gut tissues of fourth-instar G. mellonella larvae upon early exposure to a sub-lethal dose of Cry1AcF toxin. However, targeted knockdown (by using bacterially-expressed dsRNAs) of these genes led to variable effect on insect susceptibility to Cry1AcF toxin. Insects pre-treated with prohibitin and α-amylase dsRNA exhibited significant reduction in Cry1AcF-induced mortality, suggesting their probable role as Cry receptor. By contrast, insects pre-treated with GLTP, ADAM and UDP-GT dsRNA exhibited no significant decline in mortality. This maybe explained by the possibility of RNAi feedback regulation (as few of the receptors belong to multigene family) or redundant role of GLTP, ADAM and UDP-GT in Cry intoxication process. CONCLUSION: Since the laboratory culture of G. mellonella develop Bt resistance quite rapidly, findings of the current investigation may provide some useful information for future Cry receptor-related research in the model insect.

Imaging Genetic Based Mediation Analysis for Human Cognition.

The brain connectome maps the structural and functional connectivity that forms an important neurobiological basis for the analysis of human cognitive traits while the genetic predisposition and our cognition ability are frequently found in close association. The issue of how genetic architecture and brain connectome causally affect human behaviors remains unknown. To seek for the potential causal relationship, in this paper, we carried out the causal pathway analysis from single nucleotide polymorphism (SNP) data to four common human cognitive traits, mediated by the brain connectome. Specifically, we selected 942 SNPs that are significantly associated with the brain connectome, and then estimated the direct and indirect effect on the human traits for each SNP. We found out that a majority of the selected SNPs have significant direct effects on human traits and discussed the trait-related brain regions and their implications.

Freshwater Fish Siberian Dace Ingest Microplastics in the Remote Yenisei Tributary.

This study analyzed microplastics in the gastrointestinal tract of Siberian dace (Leuciscus leuciscus subsp. baicalensis (Dybowski, 1874)) in the remote Yenisei tributary of the Nizhnyaya (Lower) Tunguska River (Siberia, Russia). µRaman analysis showed that 60% of the fish from two different sites had ingested plastic microparticles (on average, 1.55 ± 1.95 items per individual). The most common type of microplastic were fibers, and the most abundant size category was 300 to 1000 µm. In the studied population, no significant differences in the MP content between the two sites or between males and females were found (p > 0.05). The tendency for higher MP ingestion by Siberian dace at earlier ages (2+ and 3+) compared to later (4+ and 5+) was observed, which may be connected to the features of the fish biology and ecology.

The induced knockdown of GmCAD receptor protein encoding gene in Galleria mellonella decreased the insect susceptibility to a Photorhabdus akhurstii oral toxin.

Photorhabdus bacteria secrete a repertoire of protein toxins that can kill the host insect. Among them, toxin complex (Tc) proteins have gained significant attention due to their wider conservation across the different bacterial genera. In our laboratory, a C-terminal domain of TcaB protein was characterized from P. akhurstii bacterium that conferred the potent oral insecticidal effect on Galleria mellonella. However, the role of insect gut receptors in the TcaB intoxication process was yet to be investigated. In the current study, we examined the transcription of candidate midgut receptors in TcaB-infected larvae and subsequently cloned a cadherin-like gene, GmCAD, from G. mellonella. GmCAD was highly transcribed in the fourth-instar larval stage and specifically in the midgut tissues. Our ligand blot and binding ELISA assays indicated that TcaB binds to the truncated peptides from the GmCAD transmembrane-proximal region with greater affinity than that from the transmembrane-distal region. Oral administration of bacterially expressed GmCAD dsRNA in G. mellonella severely attenuated the expression of target mRNA, which in turn alleviated the negative effect of TcaB on insect survival (TcaB-induced mortality in CAD dsRNA pretreated larvae reduced by 72-83% compared to control), implying the association of GmCAD in the TcaB intoxication process. Present findings form a basis of future research related to the insect gut receptor interactions with Photorhabdus toxins.

Brassica nigra essential oil: In-vitro and in-silico antibacterial efficacy against plant pathogenic and nitrifying bacteria.

The present study was aimed to examine the antibacterial potential of Brassica nigra essential oil (BNEO) against Ralstonia solanacearum, causal agent of bacterial wilt and Nitrosomonas sp., the nitrifying bacteria. In poisoned food assay, BNEO showed 100% growth inhibition of R. solancearum at ≥ 125 µg mL-1. Revalidation of findings by volatile assay employing inverted Petri plate technique exhibited 100% bacterial growth inhibition caused by vapors of BNEO, even at 50 µg mL-1 concentration. In the broth microdilution assay, the BNEO exhibited significant antibacterial activity only at higher concentrations (>500 µg mL-1). At 500 µg mL-1, BNEO showed 80% bacterial growth inhibition over control, which was at par with that of streptomycin (5 µg mL-1). In resazurin microtitre-plate assay, the maximum concentration of BNEO, at which color change occurred was 512 µg mL-1 (T9), and thus 512 µg mL-1 was concluded as the minimum inhibitory concentration (MIC). BNEO effectively inhibited the activity of Nitrosomonas spp. with 30-65% nitrification inhibition at the dose of 400 mkg-1 of Urea-N. Homology modeled protein targets assisted computational tool-based novel analysis helped to understand that the antibacterial potency of BNEO is due to preferable binding efficiency of allyl isothiocyanate (AITC), the major active ingredient of BNEO.

Deciphering the Behavioral Response of Meloidogyne incognita and Fusarium oxysporum Toward Mustard Essential Oil.

Environmental concerns related to synthetic pesticides and the emphasis on the adoption of an integrated pest management concept as a cardinal principle have strengthened the focus of global research and development on botanical pesticides. A scientific understanding of the mode of action of biomolecules over a range of pests is key to the successful development of biopesticides. The present investigation focuses on the in silico protein-ligand interactions of allyl isothiocyanate (AITC), a major constituent of black mustard (Brassica nigra) essential oil (MEO) against two pests, namely, Meloidogyne incognita (Mi) and Fusarium oxysporum f. sp. lycopersici (Fol), that cause severe yield losses in agricultural crops, especially in vegetables. The in vitro bioassay results of MEO against Mi exhibited an exposure time dependent on the lethal concentration causing 50% mortality (LC50) values of 47.7, 30.3, and 20.4 µg ml-1 at 24, 48, and 72 h of exposure, respectively. The study revealed short-term nematostatic activity at lower concentrations, with nematicidal activity at higher concentrations upon prolonged exposure. Black mustard essential oil displayed excellent in vitro Fol mycelial growth inhibition, with an effective concentration to cause 50% inhibition (EC50) value of 6.42 µg ml-1. In order to decipher the mechanism of action of MEO, its major component, AITC (87.6%), which was identified by gas chromatography-mass spectrometry (GC-MS), was subjected to in silico docking and simulation studies against seven and eight putative target proteins of Mi and Fol, respectively. Allyl isothiocyanate exhibited the highest binding affinity with the binding sites of acetyl cholinesterase (AChE), followed by odorant response gene-1 (ODR1) and neuropeptide G-protein coupled receptor (nGPCR) in Mi, suggesting the possible suppression of neurotransmission and chemosensing functions. Among the target proteins of Fol, AITC was the most effective protein in blocking chitin synthase (CS), followed by 2,3-dihydroxy benzoic acid decarboxylase (6m53) and trypsinase (1try), thus inferring these as the principal molecular targets of fungal growth. Taken together, the study establishes the potential of MEO as a novel biopesticide lead, which will be utilized further to manage the Mi-Fol disease complex.

COVID-19 associated rhino-orbital-cerebral mucormycosis: An observational study from Eastern India, with special emphasis on neurological spectrum.

AIMS: 1: Describe the epidemiology and determine risk factors for COVID-19 associated mucormycosis. 2: Elaborate the clinical spectrum of Rhino-Orbital-Cerebral Mucormycosis (ROCM), pattern of neuroaxis involvement and it's radiological correlates. METHODS: Observational study. Consecutive, confirmed cases of mucormycosis (N = 55) were included. A case of mucormycosis was defined as one who had clinical and radiological features consistent with mucormycosis along with demonstration of the fungus in tissue via KOH mount/culture/histopathological examination (HPE). Data pertaining to epidemiology, risk factors, clinico-radiological features were analysed using percentage of total cases. RESULTS: Middle aged, diabetic males with recent COVID-19 infection were most affected. New onset upper jaw toothache was a striking observation in several cases. Among neurological manifestations headache, proptosis, vision loss, extraocular movement restriction; cavernous sinus, meningeal and parenchymal involvement were common. Stroke in ROCM followed a definitive pattern with watershed infarction. CONCLUSIONS: New onset upper jaw toothache and loosening of teeth should prompt an immediate search for mucormycosis in backdrop of diabetic patients with recent COVID-19 disease, aiding earlier diagnosis and treatment initiation. Neuroaxis involvement was characterized by a multitude of features pertaining to involvement of optic nerve, extraocular muscles, meninges, brain parenchyma and internal carotid artery.

Nematicidal and Molecular Docking Investigation of Essential Oils from Pogostemon cablin Ecotypes against Meloidogyne incognita.

Root-knot nematode, Meloidogyne incognita is one of the most destructive nematodes worldwide. Essential oils (EOs) are being extensively utilized as eco-benign bionematicides, although the precise mechanism of action remains unclear. Pogostemon cablin Benth. is well-known as "Patchouli". It is native to South East Asia and known for ethno-pharmacological properties. In this study, chemical composition and potential nematicidal effect of EOs hydrodistilled from the leaves of P. cablin grown at three different locations in India were comprehensively investigated to correlate their mechanism of action for target specific binding affinities toward nematode proteins. Aromatic volatile Pogostemon essential oils (PEO) from Northern India (PEO-NI), Southern India (PEO-SI) and North Eastern India (PEO-NEI) were analyzed by Gas Chromatography-Mass Spectrometry (GC/MS) to characterize forty volatile compounds. Maximum thirty-three components were identified in PEO-NEI. Sesquiterpenes were predominant with higher content of α-guaiene (2.3-24.4 %), patchoulol (6.1-32.7 %) and α-bulnesene (5.9-27.1 %). Patchoulol was the major component in PEO-SI (32.7±1.2 %) and PEO-NEI (29.2±1.1 %), while α-guaiene in PEO-NI (24.4±1.2 %). In vitro nematicidal assay revealed significant nematicidal action (LC50 44.6-87.0 µg mL-1 ) against juveniles of M. incognita within 24 h exposure. Mortality increases with increasing time to 48 h (LC50 33.6-71.6 µg mL-1 ) and 72 h (LC50 27.7-61.2 µg mL-1 ). Molecular modelling and in silico studies revealed multi-modal inhibitive action of α-bulnesene (-22 to -13 kJ mol-1 ) and α-guaiene (-22 to -12 kJ mol-1 ) against three target proteins namely, acetyl cholinesterase (AChE), odorant response gene-1 (ODR1), odorant response gene-3 (ODR3). Most preferable binding mechanism was observed against AChE due to pi-alkyl, pi-sigma, and hydrophobic interactions. Structure nematicidal activity relationship suggested the presence of hydroxy group for nematicidal activity is nonessential, rather highly depends on synergistic composition of sesquiterpene hydrocarbons.

NMR identification of a conserved Drp1 cardiolipin-binding motif essential for stress-induced mitochondrial fission.

Mitochondria form tubular networks that undergo coordinated cycles of fission and fusion. Emerging evidence suggests that a direct yet unresolved interaction of the mechanoenzymatic GTPase dynamin-related protein 1 (Drp1) with mitochondrial outer membrane-localized cardiolipin (CL), externalized under stress conditions including mitophagy, catalyzes essential mitochondrial hyperfragmentation. Here, using a comprehensive set of structural, biophysical, and cell biological tools, we have uncovered a CL-binding motif (CBM) conserved between the Drp1 variable domain (VD) and the unrelated ADP/ATP carrier (AAC/ANT) that intercalates into the membrane core to effect specific CL interactions. CBM mutations that weaken VD-CL interactions manifestly impair Drp1-dependent fission under stress conditions and induce "donut" mitochondria formation. Importantly, VD membrane insertion and GTP-dependent conformational rearrangements mediate only transient CL nonbilayer topological forays and high local membrane constriction, indicating that Drp1-CL interactions alone are insufficient for fission. Our studies establish the structural and mechanistic bases of Drp1-CL interactions in stress-induced mitochondrial fission.

Role of intertidal microbial communities in carbon dioxide sequestration and pollutant removal: A review.

Intertidal microbial communities occur as biofilms or microphytobenthos (MPB) which are sediment-attached assemblages of bacteria, protozoa, fungi, algae, diatoms embedded in extracellular polymeric substances. Despite their global occurrence, they have not been reviewed in light of their structural and functional characteristics. This paper reviews the importance of such microbial communities and their importance in carbon dioxide sequestration as well as pollutant bioremediation. Global annual benthic microalgal productivity was 500 million tons of carbon, 50% of which contributed towards the autochthonous carbon fixation in the estuaries. Primary production by MPB was 27-234 gCm-2y-1 in the estuaries of Asia, Europe and the United States. Mechanisms of heavy metal removal remain to be tested in intertidal communities. Cyanobacteria facilitate hydrocarbon degradation in intertidal biofilms and microbial mats by supporting the associated sulfate-reducing bacteria and aerobic heterotrophs. Physiological cooperation between the microorganisms in intertidal communities imparts enhanced ability to utilize polycyclic aromatic hydrocarbon pollutants by these microorganisms than mono-species communities. Future research may be focused on biochemical characteristics of intertidal mats and biofilms, pollutant-microbial interactions and ecosystem influences.

Sorption mechanisms of pesticides removal from effluent matrix using biochar: Conclusions from molecular modelling studies validated by single-, binary and ternary solute experiments.

Sorption of atrazine (ATZ), imidacloprid (IMIDA) and azoxystrobin (AZOXY) in single-, bi- and ternary-solutes system was modelled using phosphoric acid-treated rice straw biochar (T-RSBC). The T-RSBC showed stronger sorption capacity for IMIDA in single- and bi-solute systems. The Freundlich constant (KFads) in ternary system followed the order: ATZ (222.7) < IMIDA (1314) < AZOXY (1459). Adsorption modeling and molecular dynamics suggested that non-bonding interactions between aromatic groups and electrostatic interactions with the phosphate ester group in T-RSBC played an important role. Enhanced sorption by pore-filling may be attributed to the stacking of pesticide molecules in the form of multilayer. IMIDA was predominantly sorbed by pore-filling mechanism, whereas, ATZ adsorbed by partitioning mechanism. The percent removal of three pesticides in waste water effluent followed the order: AZOXY > IMIDA > ATZ. The Freundlich isotherm based multicomponent Sheindorf-Rebuhn-Sheintuch equation's suggested that the extent of ATZ adsorption, in the presence of co-habiting pesticides, decreased with increase in number of solutes (KiATZ, Singlev> KiATZ, Binary> KiATZ, Ternary). The competitive coefficient values (αATZ/IMIDA, Ternary > αATZ/AZOXY,Ternary) revealed that ATZ adsorption in ternary system was inhibited more by the presence of IMIDA than AZOXY. Findings suggested that biochar with a large fraction of non-carbonized phase promoted non-competitive sorption.

TLR4 and TLR9 polymorphism: Probable role in susceptibility among the population of Bihar for Indian visceral leishmaniasis.

Genetic variations in the host TLRs genes play an important role in susceptibility and/or resistance to visceral leishmaniasis by altering the host-pathogen interaction. In this study, we investigated the association between polymorphisms of TLR4 (Asp299Gly, Thr399Ile) and TLR-9 (T-1237C), with susceptibility to visceral leishmaniasis. A bi-directional PCR amplification of specific alleles technique was used to characterize the distribution of TLR4 (Asp299Gly and Thr399Ile) and TLR9 (T-1237C) polymorphisms. A total of 60 samples were randomly selected from confirmed visceral leishmaniasis patients and 24 endemic healthy volunteers. The samples were genotyped and allele frequencies were determined. We observed that TLR4 Asp299Gly and Thr399Ile genotypes were more frequent in visceral leishmaniasis patients (10% and 15% respectively) compared to controls (4.2% and 8.3% respectively). However, the differences were not significant in TLR4 Asp299Gly and Thr399Ile alleles and genotypes. In the case of TLR9, we observed the frequency of T1237C genotype was higher in visceral leishmaniasis patients (43.3%) than in healthy controls (33.3%). Statistically significant differences were observed in TLR9 T1237C alleles and genotypes. We concluded that TLR9 T1237C, but not TLR4, gene polymorphisms can be regarded as contributors to visceral leishmaniasis susceptibility among the Indian population of Bihar state.